Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf85ca2a2bce78cd…

MALICIOUS

PDF

71.5 KB Created: 2021-06-10 01:37:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: b374eba20867d92bc55b887bfcfe492a SHA-1: ca23e9b2abfc90bf5bc674ea5f00ef5d9f34a8b9 SHA-256: cf85ca2a2bce78cd5fced77582d999881adf5598cfa8ef82dbbe658156c93248
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links pointing to external websites, many of which are hosted on compromised WordPress instances or disposable domains. The ML classifier strongly indicates maliciousness, and the heuristic firings suggest this PDF is part of a link farm designed to redirect users to potentially harmful content. No scripts were extracted, but the overall structure and URL patterns are indicative of a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://synerhu.ru/uplcv?utm_term=macmillan+mathematics+teacher%2527s+book+5+pdf PDF link annotation
    • https://plentis.eu/ckfinder/userfiles/files/widozazu.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/92346382237.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/befiwaduj.pdfIn PDF document text
    • https://akarchlight.com/wp-content/plugins/super-forms/uploads/php/files/3af57e21e503918ca3354bfa49ca7530/83205846456.pdfIn PDF document text
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/275ab35329f9071dfe2d92a3c002444d/61223570050.pdfIn PDF document text
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/eb56518bfd1e8a45b834f35776605a8c/vemiramewa.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/n8g93clfigfs5ppl1n9c9c6a35/zopeve.pdfIn PDF document text
    • http://kasargod.net/uploads/file/seniluxurusal.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609f1a5338b32---numodurev.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/b1dd8f623ccb415b8a74cf84894bc619/85210081326.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/b7d90527185972c06ce82ccca8664ae0/pogavisinasikozanijofegal.pdfIn PDF document text
    • https://suma.ca/upload/editor/file/56805013105.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/64718a42ad61f734211cf4e1cf8f24dc/49011652890.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/46659029260.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/sarululobixibidupomabo.pdfIn PDF document text
    • https://iominneapolis.com/wp-content/plugins/super-forms/uploads/php/files/6691d3a898a2cb8f981764a11792632e/94359561404.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/4j1kc341rm2pliis5ek7f2q2lr/pezuguxijetutazinole.pdfIn PDF document text
    • https://tenekedjieva.com/uploads/file/tafitomu.pdfIn PDF document text
    • http://travelport.pl/userfiles//file/dafulenojudo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8AE 5764 bytes
SHA-256: 8be6b34ae81631f51fa3238360e0d13013760f7568381515f4195481464da440
font_01_sfnt_off0000ec2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2A 10828 bytes
SHA-256: 26c64b03b72784fbb4bc7c5fef4f3f8812296c0a89e1135e8488997722242c99